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Functional characterization of a cloned long-term culture of differentiated multiplying thyroid follicular cells, HNTB-2 K, from a normal adult reveals the generation and secretion of constitutive thyroglobulin and the generation of adenosine 3',5'-cyclic monophosphate in response to thyrotropin. The adenosine 3',5'-cyclic monophosphate production is independent of enhanced DNA synthesis. Chromosome counting genetically characterizes the cells, indicating a normal diploid chromosome number. The long-term tissue culture method has implications on the studies of thyrotropin activation in normal and pathological human tissues.

Plasmacytoma-induction in mice is achieved by intraperitoneal introduction of plastic materials, mineral oils or alkanes, resulting in the formation of chronic granulomatous tissue. An in vitro system that reflects in vivo characteristics of plasmacytomas was developed. The successful in vitro growth of plasmacytomas was dependent on a feeder layer composed of stromal cells from initial sites of plasmacytomagenesis. This in vitro system will be useful in studying granuloma-dependent tumors.

Thrombotic thrombocytopenic purpura is a blood disorder of unknown cause characterized by bleeding into the tissues and anemia. When it occurs in children, it is called hemolytic uremic syndrome. The two diseases are referred to as thrombotic thrombocytopenic purpura-hemolytic uremic syndrome (TTP-HUS). Mortality was once virtually universal, but in 1959 exchange transfusions were performed, and mortality declined. Because the disease progresses rapidly, and many different treatments are tried at the same time, the interpretation of effects of the various treatments is very difficult. Plasma infusion therapy was suggested in 1963. From 1979 to 1990, 108 patients were treated for TTP-HUS with prednisone (a corticosteroid), or with plasmapheresis, plasma exchange and prednisone, according to the severity of the illness. Ten patients (9 percent) died, a considerable drop in mortality from earlier years. The results of the study show that the infusion of fresh-frozen plasma alone is insufficient in most patients, but some form of plasma therapy is beneficial, although it is not known how it works. Relapse was frequent with corticosteroids, calling their effectiveness into question, but corticosteroids do seem to be effective in earlier stages of the disease. Splenectomy (removal of the spleen) was performed on six patients, all of whom had adverse reactions, including one death. Splenectomy is no longer performed by the authors to treat TTP-HUS. Antiplatelet therapy was ineffective, and is also no longer administered for this disease. The high rate of relapse raises questions of type and length of therapy. Treatment requires many professional medical personnel, an average of 215 blood donors per patient, and expensive equipment. The large number of donors carries a high risk of disease transmission. (Consumer Summary produced by Reliance Medical Information, Inc.)

Platelets, which are important in clotting, are the only blood product that can be stored at room temperature. They are susceptible to bacterial infection, which can cause severe illness and death if the contaminated platelets are used for transfusions. The incidence of such contaminated transfusions increased soon after the Food and Drug Administration extended the allowable storage time to seven days, causing the agency to return its policy soon afterwards to the previous maximum storage time of five days. Septic transfusion reactions have decreased since then, but still occur at a fairly high rate. This study examined such reactions in one institution to see how their incidence might be further reduced. All patients receiving transfusions at a cancer center were monitored over a 42-month period. All septic reactions to platelet transfusion were identified and analyzed. Out of 4,200 transfusions during the study period, there were seven septic reactions to platelet transfusions. All seven patients were taking antibiotics effective against the bacteria. Fever occurred soon after the transfusions were given. Four of the seven platelet transfusions were from sources that had been stored five days. The incidence of septic reactions was five times higher for platelets stored five days than for those stored four or fewer days. Examination of the donors of the platelets revealed they were not infected, suggesting that contamination occurred during the puncturing of the skin with the needle or elsewhere in the donation process. These results indicate that septic reactions to platelet transfusion could further be reduced by reducing the allowable storage time to four days. (Consumer Summary produced by Reliance Medical Information, Inc.)

Stable Integration and Expression of a Bacterial Gene in the Mosquito Anopheles gambiae THE WORLDWIDE RESURGENCE OF malaria is due in part to drug resistance in the malaria parasite and [...]